1. Field of the Invention
The present invention relates to external panels of computer enclosures, and particularly to rear panels of computer enclosures having simple configuration and reduced electromagnetic radiation leakage.
2. Prior art
A conventional rear panel of a computer enclosure often comprises a rear wall and a rear plate. The rear wall defines a fixing opening whose shape mates with the rear plate. A plurality of parallel slots is defined in the rear plate, for extension of expansion cards therethrough. The rear plate is mounted to the rear wall at the fixing opening with screws or rivets. Unfortunately, seams between the rear wall and rear plate have gaps. Electromagnetic energy radiated by circuitry within the enclosure can leak out through the gaps. Such electromagnetic radiation interferes with other radiated signals, and can also interfere with the proper operation of other electrical equipment within and outside the enclosure. This is commonly referred to as Electromagnetic Interference (EMI).
To overcome EMI, manufacturers often add spring tabs or shims between the rear wall and rear plate. This is time-consuming, and adds to the costs of manufacturing. In addition, since the rear wall and rear plate are two separate parts joined together with screws or rivets, the overall strength of the rear panel is limited.
FIG. 3 shows a conventional rear panel 1 designed to overcome the above problems. The rear panel 1 is integrally made from a flat metal sheet. An opening 2 and a plurality of slots 3 are directly stamped from the rear panel 1. A plurality of guard boards 4 respectively covers the corresponding expansion slots 3. A bent plate 5 is stamped outwardly from one end of each expansion slot 3, thus forming a longitudinal slot 6 in the rear panel 1. A plurality of screw holes 7 is defined in the bent plate 5. A U-shaped cutout 9 is defined in a bent end 8 of each guard board 4, for aligning with the corresponding screw hole 7 of the bent plate 5.
In order to contain EMI, the rear panel 1 needs an extra plate (not shown) to cover the slot 6. Furthermore, because the rear panel 1 is substantially planar, heads of connectors (not shown) mounted to the rear panel 1 protrude outwardly from the computer enclosure. The heads are prone to be accidentally bumped and thereby loosened or damaged.
Thus, an improved rear panel of a computer enclosure which overcomes the above problems is desired.
Accordingly, an object of the present invention is to provide a rear panel of a computer enclosure which can efficiently prevent EMI.
Another object of the present invention is to provide a rear panel of a computer enclosure which has a simple structure and high overall strength.
Still another object of the present invention is to provide a rear panel of a computer enclosure which can protect electronic components such as connectors from being damaged.
To achieve the above-mentioned objects, a rear panel of a computer enclosure comprises a rear wall and a stamped portion which is integrally stamped from the rear wall. The stamped portion has an inner plate and three connection plates respectively perpendicularly connecting a left side, a right side and a top side of the inner plate to the rear wall. A window is defined in the inner plate, for extension of connectors therethrough. A plurality of parallel slots is defined through both the inner plate and the left connection plate. A bar is thus formed between every two adjacent slots. Each bar forms a rib thereon for reinforcing the overall structure of the rear panel. A plurality of L-shaped guard boards engagably covers the corresponding slots.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of a preferred embodiment of the present invention together with the attached drawings, in which: